This invention relates to a multi-blow cold forging apparatus and, more particularly, to cold forging apparatus for forming nuts.
In a typical prior art cold forging apparatus for forming nuts, the nut blank is progressively formed by a plurality of punches respectively coacting with a plurality of individual dies. The nut blank, following each forming blow at each die station, is transferred to the next station for a further blow. Typically, at the final die station, the die is mounted for rearward movement and the nut blank is simultaneously front formed by the punch and back pierced by a fixed piercing pin positioned concentrically behind the die. Whereas this apparatus, and its variants, produce a generally satisfactory finished nut, the overall speed of the apparatus is limited by the necessity of ejecting the partially formed nut blank from the die after each punching operation and then transferring the ejected blank to the next die station.